The effect of severe cryogenic plastic deformation and change in strain path on nanostructured copper through multistep cross rolling

Abstract

The trade-off between strength, ductility, and electrical conductivity of pure copper restricts its application in recent technologies and hence modification of microstructure through plastic deformation at cryogenic temperature was used to address this contradiction. In this research article, commercially available pure copper was subjected to cryogenic severe plastic deformation to obtain ultra-fine grains (UFG) through a multistep cross rolling process. The change in strain path and deformation at cryogenic temperature has a strong impact on the mechanical properties and microstructure of the rolled copper plates since rolling at cryogenic temperature suppresses the dynamic recovery and enables grain refinement. Mechanical properties such as yield strength (Ys), ultimate tensile strength (UTS), and microhardness increased by 158%, 80%, and 57% respectively. A very good optimum combination of electrical conductivity of 86% IACS and formability of 10.49 I.E. was obtained. A weak brass (Bs) oriented texture was observed due to continuous change of strain path.